Core B: Clinical recruits, assesses, and follows all participants in the ADRC Cohort. It uses well-established informant-based clinical and psychometric instruments (including the Uniform Data Set) at entry and annually thereafter to obtain clinical, cognitive, behavioral, and neurological data to carefully characterize each participant as to the presence or absence of dementia and, when present, its severity and etiology. The Core has successfully provided participants, tissue, and data to all requesting Cores and Projects since its inception in 1985 and will continue to do so in the next 5-year funding period. On a daily basis, the Core interacts directly or indirectly with every facet of the ADRC. The Core's Specific Aims in the proposed funding period are: 1. Maintain an active longitudinal Cohort of ~ 300 participants, cognitively normal and with DAT, of individuals 65 years or more by annually enrolling 30 new participants to replenish attritional loss and to serve Projects 1 and 3 of this competing renewal application. 2. Ensure that Cohort participants contribute to the imaging, biofluid, and DNA (Core F: Genetics) protocols of the ADRC and its affiliated grants and obtain autopsies in deceased participants for Core D: Neuropathology. 3. Support the Core's African American Outreach Satellite. 4. Coordinate with Core C: Data Management and Statistics to integrate data procedures and respond to data sharing initiatives. 5. Coordinate the Core A: Administration to maintain the ADRC's contributions to multicenter collaborative studies, including the National Alzheimer's Coordinating Center. 6. Interact cooperatively with Core E: Education and Information Transfer and its Rural Education and Outreach Satellite to further the educational, training, and outreach goals of the ADRC.